London, England (CNN) -- The Alaotra Grebe, a small diving bird native to Madagascar has been officially classified extinct, according to a leading bird conservation organization.

BirdLife International reported that the species, once found on Lake Alaotra, the largest lake in Madagascar, declined rapidly due to carnivorous fish being introduced to the lake and the use of nylon gill nets by local fishermen.

"No hope now remains for this species. It is another example of how human actions can have unforeseen consequences," Dr Leon Bennun, BirdLife International's director of science, policy and information said in a statement.

Invasive alien species are causing extinctions around the globe, Bennun says, and are one of the major threats not just to birds but to other wildlife.

BirdLife International's report is the latest update to the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species for birds and highlights additional cases of the negative impact of invasive species on bird life.

The status of Zapata Rail -- a blue/brown bird native to Southwest Cuba -- was upgraded to "critically endangered" due to the introduction of mongoose and exotic catfish to its marshland habitat.

In Asia and Australia, pollution of coastal wetlands is contributing to the falling populations of wading birds like the Great Knot and the Far Eastern Curlew.

The destruction of inter-tidal mudflats in Saemangeum, South Korea, an important migratory stop-over site, has seen numbers of the Great Knot fall by 20 percent, according to BirdLife.

But the news isn't all bad. Conservation projects are having a positive impact on the survival of bird species.

In particular, the Azores Bullfinch has been downgraded from "critically endangered" to "endangered" thanks to conservation work to restore its natural vegetation on its Atlantic island home.

And in Colombia, the numbers of Yellow-eared Parrot have been rising as its nesting sites are preserved and local communities take part in educational programs to learn about conservation.

Martin Fowlie, communications officer at BirdLife International told CNN: "The overall state of the world's birds is getting worse year on year. But these are two very good examples in the list this year that show conservation works.

"We have the skill and the expertise, so these things can be prevented. But we need commitments from governments to provide money to help birds and animals to survive."